Park Tool 13 mm/15 mm Double-ended Cone Wrench DCW-4

Product Details

Park Tool 13 mm/15 mm Double-ended Cone Wrench DCW-4

OK for home mechanics, but you may need to wear a glove to protect your hand for dealing with really tight cones.
laser-cut model, very much better than the old chrome-plated versions.
This is the useful size. Fits most front and rear hubs. Buy 2.